Most of what everyone has said is right, the Losi BK1/BK2 or Associated B4 are the go. I'd guess you probably have electrics already so go the factory team B4 or BK2. As I mentioned earlier Scott Pettet (ScottyP) has a good BK1 for sale at the moment.
Steer (sic) clear of anything other than Losi or Associated in 2wd. There are a couple of good 4wd's out there as well (Yokomo, BJ4x4) but they are usually more expensive.
Monaro Models do have the Associated but I think you know what the price will be like compared to OS. Sorry guys, not a big LHS supporter...
Go Tower hobbies for the Associated new or Hobbymania for the Losi new. Or just come down to the track at one of our CH meets, some of the guys usually have cars for sale or at least you could have a look at what you're in for.
EDIT: Ooops getting a little off topic here aren't we...